The invention relates to a winding machine.
Wing-type jig motion devices are particularly suitable for employment in connection with high traversing frequencies. In contrast to conventional jig motion devices, the alternating movement of the yarn is not caused by a single yarn guide moving back and forth, but instead by wings rotating in opposite directions which alternately grasp and guide the yarn. Since the wings at the end points of the traversing range are neither accelerated not decelerated, the effect of the inert mass of the yarn guide members is completely removed during yarn reversal.
The tips of the wings of the two rotors moved in opposite directions meet at defined fixed meeting points. The meeting points are distributed on the circle of rotation at even angular distances. The angular distance is a function of the number of wings of a rotor. If, for example, a rotor has two wings, it is 90 degrees. If the rotor has three wings, it is 60 degrees. The position of the polygon formed by the meeting points is a function of the relative phase relation of the two rotors. It is selected in such a way that two neighboring meeting points in the vicinity of the surface of the contact roller lie on a line extending parallel with the axis of the contact roller. These two meeting points are the reversing points of the traversing movement. The wing which respectively is moved in the section between the reversing points guides the yarn. At the end of the section it meets a wing of another rotor, which relieves it of the yarn.
In connection with known winding machines, for example in accordance with DE-OS 33 07 915, the jig motion device has been placed obliquely, so that an acute angle .alpha. is created between the two planes of rotation on the one hand and, on the other hand, the plane of the traversing triangle--viewed in the direction of the axis of the contact roller. The traversing triangle is defined by its three corner points. The two base corner points are the end points of the line in which the yarn runs up on the contact roller. The third corner point is the stationary yarn guide element which, in actual use, is mostly attached above the winding machine. The plane of the traversing triangle defined in this way generally does not exactly match the plane through which the yarn moves in the course of the traversing movement. In connection with wing-type jig motion devices this plane is mostly curved. By means of the oblique positioning of the jig motion device it is achieved that the free yarn length between the wing respectively guiding the yarn and the contact roller arranged underneath it is quite short. This favors the exact placement of the yarn on the bobbin.
In known winding machines the intersecting lines between the plane of the traversing triangle and the two planes of rotation are located parallel with the contact line of the contact roller surface with the traversing triangle, i.e. also parallel with the axis of the contact roller. Corresponding to the different distance of the two section lines from the contact line, the drag length at the reversing point to which the wings of the upper plane of rotation lead the yarn is greater than at the reversing point to which the wings of the lower plane of rotation lead the yarn. In this case the "drag length" is the free yarn length between the wing which guides the yarn to the reversing point and the point at which the yarn runs up on the contact roller. In actual operation the difference existing between the drag length at the reversing points can lead to a bobbin structure of differing quality at the two ends of the bobbin.
In the known machine the two rotors of a winding station are seated eccentrically in respect to each other. This step is used to assure a perfect yarn transfer at the ends of the traverse and is widely used in connection with wing-type traversers. The rotor wings of neighboring winding stations are arranged in the same two planes of rotation. The rotors of neighboring winding stations are driven in opposite directions, and in the one plane of rotation they have a lesser axial distance and in the other axis of rotation an axial distance increased by twice the eccentricity. If three or more winding stations are arranged next to each other, from winding station to winding station the rotors of neighboring winding stations, whose wings lie in one plane of rotation, alternatingly have a lesser axial distance and one that is increased by twice the eccentricity.
The arrangement of all wings in only two planes of rotation is stressed as being advantageous, because this makes it possible to keep both the distance between the wings and the distance between the planes of rotation and the run-up line of the yarn on the contact roller--i.e. the drag length--as short as possible. Because the rotors of neighboring winding stations, whose wings are arranged in identical planes of rotation, are driven in opposite directions, the circles of rotation of neighboring rotors--analogously to gear teeth meshing with each other--can overlap in a maximal area without hitting each other or hampering each other. The advantage of achieving a simple gear structure and in particular the synchronization of the traversing movement from one traverse to the next is ascribed to the changing axial distances between the rotors. However, the changing axial distance is a necessary result of the rotation in opposite directions of the wings of neighboring winding stations, whose rotors are seated eccentrically in respect to each other.
It is therefore possible to state in conclusion that the two advantages--short drag length and short distances between neighboring winding stations--are only achieved by tolerating disadvantages, namely different drag lengths at the two ends of the traverse and the different geometry of neighboring winding stations which, in actual operation, can lead to different bobbin structures.
A winding machine with wing-type traversing is known from DE-OS 17 10 068, which apparently has only one single winding station. In this case the axes of rotation of the two rotors form an angle with the axis of rotation of the contact roller, which slightly differs from 90.degree. and whose size is a function of the distance d existing between the two planes of rotation and the traverse H. Therefore the planes of rotation of the two wing arrangements intersect the plane of the traversing triangle at an acute angle in such a way that the drag length at one end of the traverse is of the same size as that at the other end.